Contour crafting extrusion nozzles

ABSTRACT

An automated extrusion construction system may include an extrusion nozzle configured to extrude construction material in a substantially horizontal direction against an elongated and substantially vertical surface. An extrusion nozzle may have a height adjustment mechanism configured to adjust the height of an outlet in response to level deviations in the surface on which the construction material is extruded by the extrusion nozzle. An automated extrusion construction system may include a slicing mechanism configured to controllably slice through the extruded layer.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a U.S. National Phase filing of P.C.T. ApplicationNo. PCT/US2008/080976, entitled “Contour Crafting Extrusion Nozzles,”filed 23 Oct. 2008, which is based upon and claims priority to U.S.Provisional Patent Application Ser. No. 60/982,378, entitled “Nozzlesfor Contour Crafting of Walls,” filed Oct. 24, 2007, and U.S.Provisional Patent Application Ser. No. 60/990,581, filed Nov. 27, 2007,entitled “Methods for Sensing Viscous Fluid Flow Rate,”. The entirecontent of all three applications is incorporated herein by reference.

This application is also a continuation-in-part application of thefollowing:

-   -   U.S. patent application Ser. No. 11/040,401, entitled “Robotic        Systems for Automated Construction,”, filed Jan. 21, 2005        (issued Jan. 5, 2010 as U.S. Pat. No. 7,641,461); which claims        priority to U.S. Provisional Application Ser. No. 60/537,756,        entitled “Automated Construction Using Extrusion,”, filed Jan.        20, 2004;    -   U.S. patent application Ser. No. 11/040,602, entitled “Automated        Plumbing, Wiring, and Reinforcement,”, filed Jan. 21, 2005        (issued Nov. 18, 2008 as U.S. Pat. No. 7,452,196); which claims        priority to U.S. Provisional Application Ser. No. 60/537,756,        entitled “Automated Construction Using Extrusion,”, filed Jan.        20, 2004;    -   U.S. patent application Ser. No. 11/040,518, entitled        “Mixer-Extruder Assembly,” filed Jan. 21, 2005, which claims        priority to U.S. Provisional Application Ser. No. 60/537,756,        entitled “Automated Construction Using Extrusion,”, filed Jan.        20, 2004;    -   U.S. patent application Ser. No. 11/552,885, entitled “Extruded        Wall with Rib-Like Interior,” filed Oct. 25, 2006, which claims        priority to U.S. Provisional Application No. 60/730,560,        entitled “Contour Crafting Nozzle and Features for Fabrication        of Hollow Structures,” filed Oct. 26, 2005;    -   U.S. patent application Ser. No. 11/552,741, entitled        “Deployable Contour Crafting,” filed Oct. 25, 2006, which claims        priority to U.S. Provisional Application No. 60/730,418,        entitled “Deployable Contour Crafting Machine,” filed Oct. 26,        2005;    -   U.S. patent application Ser. No. 11/556,027, entitled “Material        Delivery System Using Decoupling Accumulator,” filed Nov. 2,        2006, which claims priority to U.S. Provisional Application No.        60/733,451, entitled “Material Delivery Approaches for Contour        Crafting,” filed Nov. 4, 2005;    -   U.S. patent application Ser. No. 11/556,048, entitled “Dry        Material Transport and Extrusion,” filed Nov. 2, 2006, which        claims priority to U.S. Provisional Application No. 60/733,451,        entitled “Material Delivery Approaches for Contour Crafting,”        filed Nov. 4, 2005;    -   U.S. patent application Ser. No. 11/733,096, entitled        “Compliant, Low Profile, Independently Releasing, Non-Protruding        and Genderless Docking System for Robotic Modules,” filed Apr.        9, 2007, which claims priority to U.S. Provisional Application        No. 60/744,483, “Compliant, Low Profile, Non-Protruding, and        Genderless Docking System for Robotic Modules,” filed Apr. 7,        2006;    -   U.S. patent application Ser. No. 11/780,978, entitled “Bag        Lifting and Emptying System,” filed Jul. 20, 2007, which claims        priority to U.S. Provisional Application No. 60/807,867,        entitled “Lifting and Emptying System for Bagged Materials,”        filed Jul. 20, 2007;    -   U.S. patent application Ser. No. 11/934,507, entitled “Gantry        Robotics System and Related Material Transport for Contour        Crafting,” filed Nov. 2, 2007, which claims priority to U.S.        Provisional Application No. 60/864,293, entitled “Gantry        Robotics System and Related Material Transport for Contour        Crafting,” filed Nov. 3, 2006; and    -   U.S. patent application Ser. No. 11/933,985, entitled “Metering        and Pumping Devices,” filed Nov. 1, 2007, (issued Aug. 18, 2009        as U.S. Pat. No. 7,574,925); which claims priority to U.S.        Provisional Application No. 60/864,060, entitled “Metering and        Pumping Devices,” filed Nov. 3, 2006.

This application is also related to U.S. Pat. No. 7,153,454, entitled“Multi-Nozzle Assembly for Extrusion of Wall,” issued Dec. 26, 2006.

The entire content of all of the aforementioned patent applications andpatent is incorporated herein by reference.

BACKGROUND

1. Field

This disclosure relates to construction of structures, such as walls andbuildings. This disclosure also relates to extrusion of constructionmaterial and devices and apparatus that are involved in such a process,including extrusion nozzles.

2. Description of Related Art

Constructing homes, offices, and other structures has an ancientheritage. Despite centuries of development, however, construction canstill be very labor intensive. Even a modest sized structure may requirethe efforts of numerous workers. The appearance and quality of severalstructures built from the same design may also vary due to differencesin the skills, efforts, supervision, and techniques employed by theirbuilders. Construction may also waste material. When standardoff-the-shelf lengths of wood is used, for example, the wood may have tobe cut to meet design requirements. Construction may also be hazardous.Construction workers may be killed or seriously injured.

These problems gave rise to the nozzle assemblies disclosed in U.S. Pat.No. 7,153,454, issued Dec. 26, 2006, entitled “Multi-Nozzle Assembly forExtrusion of Wall,” as well as the related equipment and methodsdisclosed in the patent applications cited above.

These patent applications and patent collectively disclose equipment andmethods for automatically constructing buildings by extrudingconstruction material, layer by layer, from one or more extrusionnozzles. These nozzles may be manipulated by robots under computercontrol. The process has become known as “Contour Crafting.”

Such advancements have brought with them corresponding challenges. Forexample, it may be challenging to extrude walls which have multiplelayers, such as an internal core of insulation, a stucco exterior, and aplastered interior. It may also be challenging to craft openings in suchextruded walls for such components as windows and doors. It may also bechallenging to create a uniform and level base layer when the underlyingsurface is uneven.

SUMMARY

An automated extrusion construction system may include an extrusionnozzle configured to extrude construction material in a substantiallyhorizontal direction against an elongated and substantially verticalsurface. The construction system may include a nozzle positioning systemconfigured to controllably move the extrusion nozzle to differentpositions. The construction system may include a controller. Thecontroller may be configured to direct the nozzle positioning system tomove the extrusion nozzle across the substantially vertical surface in asubstantially horizontal direction while the extrusion nozzle isextruding the construction material. This may cause a substantiallyhorizontal strip of the construction material to be extruded from theextrusion nozzle onto the substantially vertical surface.

The processing system may be configured to direct the nozzle positioningsystem to repeatedly move the extrusion nozzle across the substantiallyvertical surface in the substantially horizontal direction while theextrusion nozzle is extruding the construction material. This may causea plurality of substantially stacked and substantially horizontal stripsof the construction material to be extruded from the extrusion nozzleonto the substantially vertical surface.

The extrusion nozzle may have an outlet from which the constructionmaterial is extruded. The outlet may be substantially rectangular inshape. The outlet may have a leading perimeter edge which is in thefront of and a trailing perimeter edge which is at the rear of theextrusion nozzle during its horizontal movement. The outlet may beconfigured such that the leading perimeter edge extends laterallyfurther than the trailing perimeter edge. The outlet may have a topperimeter edge which is at the top of the extrusion nozzle during itshorizontal movement. The outlet may be configured such that the topperimeter edge extends laterally further than both the leading andtrailing perimeter edges.

The substantially vertical surface may be part of a structure that has asubstantially horizontal upper surface. The processing system may beconfigured to cause an upper portion of the outlet to extend above thehorizontal surface while the extrusion nozzle moves across thesubstantially vertical surface in the substantially horizontaldirection.

An extrusion nozzle assembly may include a first extrusion nozzleconfigured to extrude construction material in a first substantiallyhorizontal direction against a first elongated and substantiallyvertical surface. The extrusion nozzle assembly may include a secondextrusion nozzle configured to extrude construction material in a secondsubstantially horizontal direction that is substantially opposite of thefirst substantially horizontal direction against a second elongated andsubstantially vertical surface that is substantially parallel to andspaced apart from the first vertical surface.

The extrusion nozzle may include an actuator mechanism configured tocontrollably move the second extrusion nozzle from an extrusion positionat which the second extrusion nozzle is positioned to extrude theconstruction material in the second substantially horizontal directionto a non-extrusion position at which the second extrusion nozzle is notpositioned to extrude the construction material in the secondsubstantially horizontal direction. The non-extrusion position may besuch as to prevent the second extrusion nozzle from contacting aninterior corner of the second vertical surface while the first extrusionnozzle extrudes the construction material against an outer corner of thefirst vertical surface.

The extrusion nozzle may include a valve configured to cut off flow ofthe construction material to the second extrusion nozzle when the secondextrusion nozzle is in the non-extrusion position.

An automated extrusion construction system may include a first extrusionnozzle configured to extrude a first construction material so as to forma substantially horizontal extruded layer having an elongated andsubstantially vertical surface. The automated extrusion constructionsystem may include a second extrusion nozzle configured to extrude asecond construction material in a substantially horizontal directionagainst the vertical surface so as to form a substantially horizontalstrip of the second construction material on the vertical surface. Theautomated extrusion construction system may include a nozzle positioningsystem configured to controllably move the first and second extrusionnozzles to different positions. The automated extrusion constructionsystem may include a controller. The controller may be configured todirect the nozzle positioning system to move the first extrusion nozzlein the substantially horizontal direction so as to form thesubstantially horizontal extruded layer and to move the second extrusionnozzle in the substantially horizontal direction against the verticalsurface so as to form the substantially horizontal strip.

The controller may be configured to direct the nozzle positioning systemto cause the second extrusion nozzle to move in synchronism with andbehind the first extrusion nozzle. This may cause the second extrusionnozzle to extrude the substantially horizontal strip on thesubstantially vertical surface of the horizontal extruded layer extrudedduring the same horizontal traverse by the first extrusion nozzle.

The first extrusion nozzle may be configured to cause at least onelongitudinal channel to be formed in the vertical surface of theextruded layer. The second extrusion nozzle may be configured to extrudethe horizontal strip with a longitudinal locking bead that interlockswith the longitudinal channel.

The automated extrusion construction system may include a slicingmechanism configured to controllably slice through the extruded layer.The positioning system may be configured to controllably move theslicing mechanism to different positions. The controller may beconfigured to direct the positioning system to move the slicingmechanism so as to slice through the extruded layer in a direction thatis substantially perpendicular to the horizontal direction at a firstset of two spaced-apart locations.

The controller may be configured to direct the positioning system tomove the extrusion nozzle in a substantially horizontal direction so asto form a second substantially horizontal extruded layer substantiallyon top of the first horizontal extruded layer. The controller may beconfigured to direct the positioning system to move the slicingmechanism so as to slice through the second extruded layer at twospaced-apart locations, each immediately above one of the twospaced-apart locations in the first set of spaced-apart locations.

The slicing mechanism may include a cutting blade and/or a cuttingcable.

The slicing mechanism may be attached to the extrusion nozzle.

The automated extrusion construction system may include an actuatormechanism configured to move the slicing mechanism between a cuttingposition at which the slicing mechanism is oriented to slice through theextruded layer and a non-cutting position at which the slicing mechanismis oriented so as to avoid cutting through the extruded layer while itis being extruded by the extrusion nozzle.

The slicing mechanism may be configured to vibrate while slicing.

A process for constructing a wall having a rectangular opening thereinmay include extruding a substantially horizontal layer of constructionmaterial and covering the upper surface of the extruded layer across theportion thereof which lies at the bottom of the desired rectangularopening with a layer of anti-adhesion material. The process may includeextruding one or more additional substantially horizontal layers ofconstruction material, each on top of the preceding extruded layer,until the top of the last extruded layer substantially coincides withthe top of the rectangular opening. The process may include slicingthough each of the one or more additional extruded layers at locationswhich coincide with the left and right sides of the rectangular openingsafter each of the one or more additional extruded layer are extruded butbefore the next later is extruded. The process may include covering theupper surface of the last extruded layer across the portion thereofimmediately below the top of the desired rectangular opening with alayer of anti-adhesion material. The process may include extruding oneor more additional substantially horizontal layers of constructionmaterial, each on top of the preceding extruded layer. The process mayinclude pushing out the block of extruded layers at the location of therectangular opening, thus creating the rectangular opening in the wall.

The anti-adhesion material may be plastic.

The anti-adhesion material may be sprayed on.

The slicing may be performed with a vibrating slicing mechanism.

A wall may have a rectangular opening therein. The wall may have one ormore stacked layers of extruded construction material below therectangular opening. The wall may have one or more stacked layers ofextruded construction material to the right and to the left of therectangular opening substantially spanning the height of the rectangularopening. The wall may have one or more stacked layers of extrudedconstruction material above the rectangular opening, whereby the top ofthe rectangular opening constitutes the extruded layer immediately aboveit and does not contain a non-extruded horizontal header which spans awidth greater than the size of the rectangular opening.

The opening may be sized for a window or a door.

An extrusion nozzle may include an outlet configured to extrudeconstruction material in a substantially horizontal direction. Theoutlet may have an adjustable height. The extrusion nozzle may have aheight adjustment mechanism coupled to the outlet and configured toadjust the height of the outlet in response to level deviations in thesurface on which the construction material is extruded by the extrusionnozzle.

The height adjustment mechanism may include at least one wheelconfigured to ride on top of the surface on which the constructionmaterial is extruded while the construction material is extruded fromthe outlet. The outlet may have a bottom edge and the wheel may have aradius which is large enough to cause the perimeter of the wheel toprotrude beneath the bottom edge of the outlet.

The outlet may include two portions that are configured to slide withrespect to one another and to vary the height of the outlet based ontheir relative position with respect to one another.

The extrusion nozzle may include at least one spring configured to urgethe two portions apart from one another so as to maximize the height ofthe outlet when no external force is applied between the two portions.

An automated extrusion construction system may include a controllerconfigured to direct a nozzle positioning system to move an extrusionnozzle in a substantially horizontal direction while the extrusionnozzle is extruding the construction material so as cause asubstantially horizontal strip of the construction material to beextruded from the extrusion nozzle that has an upper surface that is ata uniform level and a lower surface that substantially tracks the leveldeviations in the surface on which the construction material isextruded.

An extruded strip of construction material may have an upper surfacethat is at a uniform level and a lower surface that substantially tracksdeviations in a surface on which the extruded strip is resting. Theextruded strip may have been formed without the aid of a mould.

A process for extruding construction material onto a surface that haslevel deviations comprising moving an extrusion nozzle in asubstantially horizontal direction while extruding the constructionmaterial from an outlet in the extrusion nozzle so as to cause the uppersurface of the extrudate to be at a substantially uniform level and thelower surface of the extrudate to substantially track the leveldeviations in the surface below, all without using a mould to containboth of the sides of the extruded material after it is extruded from theextrusion nozzle.

The width of the extrudate may be substantially constant along itslength.

The process may include traversing the extrusion nozzle across the samehorizontal path a plurality of times at different vertical levels whileextruding the construction material therefrom so as to form a wallhaving a level top and a bottom that substantially tracks the leveldeviations in the surface below.

These, as well as other components, steps, features, objects, benefits,and advantages, will now become clear from a review of the followingdetailed description of illustrative embodiments, the accompanyingdrawings, and the claims.

BRIEF DESCRIPTION OF DRAWINGS

The drawings disclose illustrative embodiments. They do not set forthall embodiments. Other embodiments may be used in addition or instead.Details that may be apparent or unnecessary may be omitted to save spaceor for more effective illustration. Conversely, some embodiments may bepracticed without all of the details that are disclosed. When the samenumeral appears in different drawings, it is intended to refer to thesame or like components or steps.

FIG. 1( a) illustrates an extrusion nozzle configured to extrude aninternal extruded layer.

FIG. 1( b) illustrates the extrusion nozzle illustrated in FIG. 1( a)extruding an internal extruded layer.

FIG. 2( a) illustrates an extrusion nozzle with a slicing mechanism thatincludes a cutting blade and an associated actuator mechanism.

FIG. 2( b) illustrates the extrusion nozzle illustrated in FIG. 2( a)cutting an extruded layer.

FIGS. 3( a)-3(g) illustrate an extrusion nozzle and an associatedslicing mechanism being used to form an opening in an extruded wallformed from stacked extruded layers.

FIGS. 4( a) and 4(b) illustrate an extrusion nozzle with a slicingmechanism that includes a cutting cable and an associated actuatormechanism.

FIG. 5( a) illustrates an extrusion nozzle configured to extrude anextruded layer that has a level top surface and a depth that conforms tocontours of an uneven ground surface below.

FIG. 5( b) illustrates a fixed portion of an outlet that forms a part ofthe extrusion nozzle illustrated in FIG. 5( a).

FIG. 6( a) illustrates an extrusion nozzle configured to extrude aextruded surfacing layer laterally onto the side of a surface.

FIGS. 6( b) and 6(c) illustrate the extrusion nozzle illustrated in FIG.6( a) extruding a stacked extruded surfacing layer onto the side ofanother stacked extruded layer.

FIG. 6( d) illustrates one of the extruded surfacing layers illustratedin FIGS. 6( b) and 6(c) being extruded by the extrusion nozzleillustrated in FIG. 6( a).

FIG. 7( a) illustrates a stacked internal extruded layer being extrudedby an extrusion nozzle and a stacked extruded surfacing layer beingextruded on both the inside and outside of the stacked internal extrudedlayer by a different dual extrusion nozzle assembly.

FIGS. 7( b)-7(d) illustrate the stacked extrudate surfacing layerillustrated in FIG. 7( a) being extruded by the dual extrusion nozzleassembly while turning a corner.

FIG. 8 illustrates an internal shut-off valve that may be used in thedual extrusion nozzle assembly illustrated in FIGS. 7( a)-7(d).

FIGS. 9( a) and (b) illustrate an extrusion nozzle configured to extrudean extruded surfacing layer that has a level top surface and a depththat conforms to contours of an uneven ground surface below.

FIG. 10 is a block diagram of a automated extrusion construction system.

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Illustrative embodiments are now discussed. Other embodiments may beused in addition or instead. Details that may be apparent or unnecessarymay be omitted to save space or for a more effective presentation.Conversely, some embodiments may be practiced without all of the detailsthat are disclosed.

FIG. 1( a) illustrates an extrusion nozzle configured to extrude aninternal extruded layer. An extrusion nozzle 101 may include an inlet103, a tube 105, a housing 107 which has an outlet 109, side trowels 111and 113, a rear wall 115, side trowels 117 and 119, and channelprotrusions 121, 123, 125 and 127.

Construction material, such as cementitious material, foam, plaster,stucco, may be delivered in a viscous fluidic state into the inlet 103.This material may then be extruded through the outlet 109. The sidetrowels 117 and 119 may serve to shape the extrudate, along with thechannel protrusions 121, 123, 125, and 127.

The construction material which is delivered to the inlet 103 may bemixed with a hardener that causes it to harden after it is extruded fromthe outlet 109. One or more additives may be mixed with the constructionmaterial in order to accelerate or de-accelerate the hardening time.

FIG. 1( b) illustrates the extrusion nozzle illustrated in FIG. 1( a)extruding an extruded layer. As illustrated in FIG. 1( b), the extrusionnozzle 101 may extrude an extruded layer 131. The extruded layer 131 maybe substantially horizontal and may have an upper surface 136 that isalso substantially horizontal. The extruded layer 131 may include one ormore longitudinal channels, such as longitudinal channels 135, 137, 139,and 141. These channels may be used for interlocking with surfacinglayers that may be applied to the vertical surfaces of the extrudedlayer 131, as will become more clear in connection with the discussionof FIGS. 7( a)-7(d) below. The extruded layer 131 may instead not haveany longitudinal channels and/or may be configured to stand without anysurfacing layers or with only a single surfacing layer. The extrudedlayer 131 may be oriented other than in a horizontal position.

The number, position, and cross-section of the longitudinal channels135, 137, 139, and 141 may vary. The number, position and shape of thecorresponding channel protrusions 121 and 123 in the side trowel 117 andthe channel protrusions 125 and 127 in the side trowel 119 may vary tomatch. For example, the trowels 117 and 119 may be configured to provideno longitudinal channels, to provide longitudinal channels having adifferent cross-section, to provide longitudinal channels on only onevertical face of the extruded layer 131, or to provide no longitudinalchannels. The upper trowel may similarly be configured with one or moreprotrusion to provide longitudinal channels in the top surface of theextruded layer 136.

The shape and position of the side trowels 117 and 119 and the uppertrowel 129 and their associated protrusions are illustrated as beingfixed. In other configurations, one or more server motors, solenoids,pneumatic actuators, hydraulic actuators, or other controlled devicesmay be used to make them adjustable. Manually-adjustable mechanisms maybe used instead.

The extrusion nozzle 101 may move in a horizontal direction along astraight line, as illustrated in FIG. 1( b). It may instead be moved inother directions and/or along pathways which are not linear, thuscreating extruded layers which themselves are not linear or horizontal.

FIG. 2( a) illustrates an extrusion nozzle with a slicing mechanism thatincludes a cutting blade and an associated actuator mechanism. FIG. 2(b) illustrates the extrusion nozzle illustrated in FIG. 2( a) cutting anextruded layer.

As illustrated in FIG. 2( a), an extrusion nozzle 201 may include acutting blade 203 controlled by an actuator mechanism 205. The extrusionnozzle 201 may be of the type illustrated in FIG. 1( a) or may be of anyother type.

The extrusion nozzle 201 may be operated so as to extrude constructionmaterial, thereby forming an extruded layer 207. During this process,the actuator mechanism 205 may cause the cutting blade 203 to be in anon-cutting position during which the extrusion nozzle 201 may extrudethe construction material without interference from the cutting blade203.

After the extruded layer 207 is extruded, the actuator mechanism maycause the cutting blade 203 to move from the non-cutting position to acutting position at which the cutting blade 203 may be oriented to slicethrough the extruded layer 207, as illustrated in FIG. 2( b). While inthis position, the extrusion nozzle 201 may be moved immediately abovethe extruded layer 207 and may then be caused to traverse across it,thereby slicing an undesirable portion 209 from the extruded layer 207,as illustrated in FIG. 2( b). During this slicing operation, thedelivery of construction material to an inlet 211 of the extrusionnozzle may be halted.

The cutting blade 203 may be attached to the extrusion nozzle 201, asillustrated in FIGS. 2( a) and 2(b). It may instead be separate from theextrusion nozzle 201 and operated independently so as to effectuate thesame slicing action as is illustrated in FIG. 2( b).

The actuator mechanism 205 may be of any type. For example, it may beconfigured to longitudinally slide the cutting blade 203 from anelevated position to a lowered position, as illustrated in FIGS. 2( a)and 2(b), respectively. The actuator mechanism 205 may instead beconfigured to rotate the cutting blade 203 from its elevated position toits lowered position. Any type of device may be used for the actuatormechanism, such as a server motor, solenoid, pneumatic actuator,hydraulic actuator, and/or any combination of these.

FIGS. 3( a)-3(g) illustrate an extrusion nozzle and an associatedslicing mechanism being used to form an opening in an extruded wallformed from stacked extruded layers. As illustrated in FIG. 3( a), anextrusion nozzle 301 may be used to extrude a first extruded layer 303.The extrusion nozzle 301 may be of the type illustrated in FIG. 1( a) ormay be of any other type. The extruded layer 303 may be of any size orconfiguration.

After the first extruded layer 303 is extruded, an anti-adhesion layer305 may be applied to the upper surface of the first extruded layer 303across the portion thereof which lies at the bottom of the desiredrectangular opening that is to be formed, as illustrated in FIG. 3( b).The anti-adhesion layer 305 may be of any type of material that reducesthe tendency of a second extruded layer that is extruded on top of thefirst extruded layer 303 to stick to the upper surface of the firstextruded layer 303 at the location of the anti-adhesion layer 305. Forexample, the anti-adhesion layer 305 may be plastic or wax. Theanti-adhesion layer may be applied by spraying. It may instead be asheet of material that is placed at the appropriate location. Theanti-adhesion layer 305 may be applied by automated or by manual means.

A second extruded layer 307 may be extruded from the extrusion nozzle301 directly above the first extruded layer 303, as illustrated in FIG.3( c). Thereafter, an actuator mechanism 309 that may be part of theextrusion nozzle 301 may be operated to cause a slicing mechanism, suchas a cutting blade 311, to move from the non-cutting positionillustrated in FIG. 3( a) to the cutting position illustrated in FIG. 3(c). The actuator mechanism 309 and the cutting blade 311 may be of thesame type as illustrated in FIG. 2( a) or may be of any other type.

While in the cutting position, the extrusion nozzle 301 may be movedtransverse to the second extruded layer 307 at two spaced-apartlocations that correspond to the location of the sides of the desiredrectangular opening, thereby slicing the second extruded layer 307 atthese locations, as illustrated in FIG. 3( c).

Additional extruded layers may be successively extruded and successivelysliced by the extrusion nozzle 301. This may include a third extrudedlayer 310, as illustrated in FIG. 3( d). As illustrated in FIG. 3( e),it may include a fourth extruded layer 311, a fifth extruded layer 313,and a sixth extruded layer 315. These extruded layers may besuccessively applied and successively sliced, as illustrated in FIG. 3(e), until the top surface of the last extruded layer is at the top ofthe desired rectangular opening.

At this point, a second anti-adhesion layer 317 may be applied to thetop surface of the last extruded layer immediately below the top of thedesired rectangular opening, as illustrated in FIG. 3( e). Theanti-adhesion layer 317 may be any of the types and may be applied byany of the methods discussed above in connection with the anti-adhesivelayer 305.

Thereafter, one or more additional extruded layers may be extruded ontop of the last extruded layer by the extrusion nozzle 301, asillustrated by a seventh extruded layer 319 in FIG. 3( f). After theextrusions harden, the cut rectangle of extruded material which liesbetween the two non-adhesion layers 305 and 317 may be pushed out of thewall which has been extruded, leaving a rectangular opening 321illustrated in FIG. 3( g). The pushing may be done by automated ormanual means.

The wall which remains in FIG. 3( g) may consists of a plurality ofstacked layers of extruded construction material below the rectangularopening 321. The wall may have one or more stacked layers of extrudedconstruction material to the right and left of the rectangular opening321 that substantially span the height of the rectangular opening. Thewall may have one or more stacked layers of extruded constructionmaterial above the rectangular opening 321. The top of the rectangularopening 321 may itself be formed of an extruded layer, such as theseventh extruded layer 319. Using this construction procedure, it may beunnecessary to place a non-extruded horizontal header above the top ofthe rectangular opening 321 and which extends beyond the opening inorder to extrude layers above it.

The rectangular opening 321 may be sized to accommodate constructioncomponents of any size, such as a door or a window. Once inserted, theframe of the door, window, or other component may provide additionalstructural support.

The slicing mechanism has thus-far been illustrated as being a cuttingblade, such as the cutting blade 203 in FIG. 2( a) and the cutting blade311 in FIG. 3( c). Other types of slicing mechanisms may be used inaddition or instead. For example, a cutting cable may be used.

FIGS. 4( a) and 4(b) illustrate an extrusion nozzle with a slicingmechanism that includes a cutting cable and an associated actuatormechanism. As illustrated in FIGS. 4( a) and 4 (b), an extrusion nozzle401 may have attached to it a cutting cable 403 attached to theextrusion nozzle 401 by a frame 405 through an actuator mechanism 409.

The extrusion nozzle 401 may be the same as the extrusion nozzle 101illustrated in FIG. 1( a) or may be of any other type. The cutting cable403 may be made of any material such as steel. It may be saw-toothed,rough, or it may be smooth.

As illustrated in FIGS. 4( a) and 4(b), the actuator mechanism 409 maybe configured to move the cutting cable 403 between a non-cuttingposition at which the slicing mechanism is oriented so as to avoidcutting through an extruded layer while it is being extruded by theextrusion nozzle 401 and a cutting position at which the slicingmechanism is oriented to slice through extruded layer. The actuatormechanism 409 may accomplish this by rotating the frame 405 along ahorizontal axis which is either perpendicular or parallel to thedirection the extrusion nozzle 401 is moved to extrude an extruded layer411. All other aspects of the extrusion nozzle 401 and actuatormechanism 409 may be the same as were discussed above in connection withthe extrusion nozzles 201 and 301 and actuator mechanism 309,respectively.

The time during which the slicing mechanism slices the extruded layermay vary. In some configurations, the slicing mechanism may be directedto slice the extruded layer immediately after it is extruded. In otherconfigurations, the slicing may be delayed until the extruded layerpartially solidifies. In still other configurations, the slicingmechanism may be directed to slice after the extruded layer completelysolidifies.

A vibration system may be used to cause the slicing mechanism to vibratewhile it is slicing the extruded layer. In some configurations, thevibrating mechanism may be incorporated into the actuator mechanism,such as into the actuator mechanism 205 and/or the actuator mechanism409. In other configurations, the vibration system may be separate.

The vibration system may be configured to cause the slicing system tovibrate in only one direction. For example, the vibrating system may beconfigured to cause the slicing mechanism to vibrate along the directionof slicing, so as to minimize deformation of an unhardened extrudedlayer during slicing. In other configurations, the vibrating system maybe configured to vibrate the slicing mechanism in the direction of thelongitudinal extruded layer so as to create a gap between the slicedportions of the layer, thereby reducing the chance that the slicedportions will reattach to one another after the slicing mechanism isremoved and while the curing process continues. In other configurations,the vibration system may be configured to cause the slicing mechanism tovibrate along the axis of the slicing member. In other configurations,the vibration system may be configured to cause the slicing mechanism tovibrate in a multiple directions, such as in two or more of thesedirections.

The slicing mechanism may be used for other purposes in addition orinstead. For example, the slicing mechanism may be used to constructprefabricated walls that are made of extruded layers at a factory. Afterthe extrusion of each layer, the slicing mechanism may be used to squarethe beginning and/or end portion of the extruded layer. The slicingmechanism may similarly be used to square the ends of each cascadingextruded layer, thereby helping to create a wall module that has squaredsides. This squaring process may be used on site as well as in makingprefabricated structures off site.

The slicing mechanism may be used for other purposes in addition orinstead. For example, the slicing mechanism may be used to sliceprefabricated structures that are made of extruded layers at a factoryinto portions that can be more readily shipped as compared to the entirestructure. After the extrusion of each layer of the structure, theslicing mechanism may be used to slice the structure at the locations atwhich the structure is to be divided for shipment purposes. This slicingmay be done before each extruded layer fully hardens.

FIG. 5( a) illustrates an extrusion nozzle configured to extrude anextruded layer that has a level top surface and a depth that conforms tothe contours of an uneven ground surface below. FIG. 5( b) illustrates afixed portion of an outlet that forms a part of the extrusion nozzleillustrated in FIG. 5( a).

As illustrated in FIG. 5( a), an extrusion nozzle 501 may have an outlet503. The extrusion nozzle 501 may be of any type. For example, it may beof the type illustrated in FIG. 1( a). The outlet 503 may have a fixedoutlet portion 505 having an inlet 507 to a tube 509 and a lowerrectangular outlet 511. The outlet 503 may have a floating outletportion 513. The fixed outlet portion 505 may slide with respect to thefloating outlet portion 513 in a way which causes the height of theoutlet 503 to vary based on the relative position between the fixedoutlet portion 505 and the floating outlet portion 513.

The extrusion nozzle 501 may include a height adjustment mechanism thatis coupled to the outlet 503 and is configured to adjust the height ofthe outlet 503 in response to level deviations in the surface on whichthe construction material is extruded by the extrusion nozzle 501. Theheight adjustment mechanism may include a wheel 515 on one side of thenozzle and a corresponding second wheel (not visible in FIG. 5( a)) onthe other side. The wheels may have a radius which is large enough tocause the perimeter of the wheels to protrude beneath the bottom edge ofthe outlet 503, as illustrated in FIG. 5( a).

The height adjustment mechanism may include arms 517 and 119 attached tothe floating outlet portion 513, arms 521 and 523 attach to the fixedoutlet portion 505, and springs 525 and 527 supported on rods 529 and530, respectively. The rods 529 and 530 may be fixedly attached to thearms 517 and 519, respectively, while they may slidingly engage the arms521 and 523.

The extrusion nozzle 501 may be connected to a nozzle positioning systemthat may cause the extrusion nozzle to move in a substantiallyhorizontal direction, as illustrated in FIG. 5( a). During thismovement, an extruded layer 533 may be extruded and may have a topsurface 534 that remain at a constant level, notwithstanding deviationsin the level of the surface on which the extruded layer 533 is extruded.This may be facilitated by a lower edge 531 on the fixed outlet portion505 that remains at a constant level by virtue of it being part of thefixed outlet portion 505 which may be fixedly attached to the nozzlepositioning system.

On the other hand, the lower surface 536 of the extruded layer 533 maysubstantially track the level deviations on the surface on which theconstruction material is extruded. Deviations in this level may betransmitted through the wheels to the floating outer portion 513 andcause it's position to substantially track deviations in the level ofthe surface. In turn, this may cause corresponding variations in theoverall height of the outlet 503 by causing overall variations in thedepth of its side walls.

The small distance between the bottom of the wheel 515 and the bottomedge of the floating outlet portion 513 may help ensure that thefloating outlet portion 513 does not collide with the surface belowduring horizontal traverses, notwithstanding softness in the surfacebelow that may cause the bottom of the wheel 515 to become partiallysubmerged beneath that surface as it travels horizontally.

The springs 525 and 527 may be configured and oriented to urge the wheel515 and the other corresponding wheel to remain in contact with thesurface below as the extrusion nozzle is traversed horizontally,notwithstanding level deviations in the surface below.

The extrusion nozzle 501 may instead have only a single spring and onlya single wheel. In this case, the single spring and wheel may becentered along the base of the extrusion nozzle 501, rather than at oneend or the other. The outlet and/or height adjustment mechanism may alsobe differently configured and/or may have different components.

FIG. 6( a) illustrates an extrusion nozzle configured to extrude anextruded surfacing layer laterally onto the side of a substantiallyvertical surface. FIG. 6( b) illustrates the extrusion nozzleillustrated in FIG. 6( a) extruding stacked extruded surfacing layersonto the side of other stacked extruded layers.

As illustrated in FIG. 6( a), an extrusion nozzle 601 may include a tube604, an inlet 605 for construction material, and an outlet 605. Theoutlet may include a leading trowel 607 having a leading perimeter edge609, a trailing trowel 611 having a trailing perimeter edge 613, a toptrowel 615 having a top perimeter edge 617, and a lower trowel 619having a trowel surface 621.

As illustrated in FIG. 6( a), the leading perimeter edge 609 may extendlaterally further than the trailing perimeter edge 613. A top perimeteredge 617 may extend laterally further than both the leading perimeteredge 609 and the trailing perimeter edge 613. The trowel surface 621 ofthe lower trowel 619 may be at the same level as the trailing perimeteredge 613.

FIGS. 6( b) and 6(c) illustrate the extrusion nozzle illustrated in FIG.6( a) extruding a stacked extruded surfacing layer onto the side ofanother stacked extruded layer. FIG. 6( d) illustrates one of theextruded surfacing layers illustrated in FIGS. 6( b) and 6(c) beingextruded by the extrusion nozzle illustrated in FIG. 6( a).

As illustrated in FIGS. 6( b) and 6(c), the extrusion nozzle 601 may bemoved in a substantially horizontal direction across a substantiallyvertical surface of a second extruded layer 625.

The extrusion nozzle 601 may be positioned so as to cause an upperportion 627 of the outlet 605 to extend above a substantially horizontalupper surface 629 of the second extruded layer 625, thereby allowingexcessive extrudate to escape, thus forming an extruded overflow lip631. Otherwise, variations in the flow of the construction materialand/or in the smoothness of the substantially vertical surface 634 onthe second extruded layer 625 might cause deviations in the thickness ofthe surfacing extrusion which is extruded. The top trowel 615 may helpsmoothen the overflow material. The leading trowel 607 may help ensurethat construction material does not escape in front of the extrusionnozzle during its horizontal traverse.

As illustrated in FIGS. 6( b) and 6(c), the extrusion nozzle 601 may beused to face an entire side of an extruded wall, layer by layer. Thismay be accomplished, for example, by first extruding a first extrudedlayer 633. This may be done using an extrusion nozzle such as theextrusion nozzle 101 illustrated in FIG. 1( a) or the extrusion nozzle501 illustrated in FIG. 5( a).

The extrusion nozzle 601 may then be used to extrude a first extrudedsurfacing layer 635 on the vertical surface of the first extruded layer633. The second extruded layer 625 may then be extruded on top of thefirst extruded layer 633, such as by using the extrusion nozzle 101. Asecond extruded surfacing layer 637 may then be extruded by theextrusion nozzle 601. This process of alternating between the extrusionof a core extruded layer followed by an extruded surfacing layer on thatcore extruded layer may continue until the extruded wall reaches adesired height. In addition to accommodating for overflow, therebyminimizing non-uniformities in the extruded surfacing layers, theextruded overflow lip 631 may serve to increase the adhesion of eachextruded surfacing layer to the face of the corresponding verticalsurface on which it has been extruded. The lower trowel 619 may serve tosmoothen the seam between each stacked extruded surfacing layer.

FIG. 7( a) illustrates a stacked internal extruded layer being extrudedby an extrusion nozzle and a stacked extruded surfacing layer beingextruded on both the inside and outside of the stacked internal extrudedlayer by a different dual extrusion nozzle assembly.

As illustrated in FIG. 7( a), an extrusion nozzle 701 may be used toextrude an internal extruded layer. The extrusion nozzle 701 may be ofthe type illustrated in FIG. 1( a) or may be of any other type. It mayinclude channel protrusions so is to create one or more longitudinalchannels in the vertical surfaces of the extruded layer, such aslongitudinal channels 703 and 705.

A dual extrusion nozzle assembly 707 may also be provided. This may havea common construction material inlet 709 to a main tube 711 that isconnected to a routing chamber 713. The routing chamber 713 may directthe construction material through a first routing tube 715 to firstextrusion nozzle 719 and through a second routing tube 721 to a secondextrusion nozzle 723. The extrusion nozzles 719 and 723 may be of thetype illustrated in FIG. 6( a) or may be of any other type.

The dual extrusion nozzle assembly 707 may be controlled by apositioning system which causes it to move in synchronism with andshortly behind the extrusion nozzle 701. The construction material thatis extruded by the extrusion nozzle 701 may or may not have acomposition that causes it to solidify very quickly.

As illustrated in FIG. 7( a), several internal extruded layers may beextruded, one on top of the other, such as internal extruded layers 725,727 and 729, followed by the extrusion of a surfacing layer on bothsides of each, such as surfacing layers 731, 735, 737, 739, 741, and745. As discussed above in connection with FIGS. 6( b) and (c), eachsurfacing layer may be extruded immediately following the extrusion ofthe internal extruded layer to which it is applied. The extrusion of thesurfacing layers may also result in protruding beads which match withthe corresponding longitudinal channels.

The dual exclusion nozzle assembly 707 may be configured so as to causethe extrusion nozzles 719 and 723 to extrude construction material indirections that are substantially opposite of one another. Although theouter walls of the internal extruded layers 725, 727 and 729 areillustrated in FIG. 7( a) as being parallel, they may in othersituations not be parallel. In such a situation, the extrusion nozzles719 and 723 may be oriented so as to extrude opposing surfacing layersthat also are not parallel.

FIGS. 7( b)-7(d) illustrate the stacked extruded surfacing layerillustrated in FIG. 7( a) being extruded by the dual extrusion nozzleassembly while turning a corner. For simplicity, the leading extrusionnozzle 701 has been omitted. As illustrated in FIG. 7( b), the extrusionnozzle 723 has been moved from the extrusion position illustrated inFIG. 7( a) to a non-extrusion position. The non-extrusion position maybe such as to prevent the extrusion nozzle 723 from contacting aninterior corner of the structure which is being extruded while theextrusion nozzle 719 continues to extrude the construction materialagainst an outer corner of that structure, as illustrated in FIGS. 7( b)and 7(c). To facilitate this, the extrusion nozzle may include acontrollable pivot configured to allow the nozzle to controllably pivotwith respect to the nozzle positioning system. The extrusion nozzle 723may be moved back to the extrusion position so as to continue extrudingthe extruded surfacing layer on the interior of the structure once it isappropriated to do so, as illustrated in FIG. 7( d).

An actuator mechanism (not visible) may be provided that causes theextrusion nozzle 723 to move from the extrusion position to thenon-extrusion position. A separate actuator may similarly be providedthat causes the extrusion nozzle 719 to move from the extrusion positionillustrated in FIGS. 7( a)-7(d) to a non-extrusion position thatprevents contact between the extrusion nozzle 719 and an interior cornerof a different structure that may also be extruded.

The actuator mechanisms that are used with the extrusion nozzles 723 and719 may be of any type. For example, the actuator mechanisms may includeone or more server motors, solenoids, numanic actuators, and/orhydraulic actuators. The actuator mechanisms may be located within therouting chamber 713 and/or elsewhere.

FIG. 8 illustrates an internal shut-off valve that may be used in thedual extrusion nozzle assembly illustrated in FIGS. 7( a)-7(d). Asillustrated in FIG. 8, the valve 801 may be located within the routingchamber 713. The valve 801 may include a valve door 803 and acorresponding valve closure surface 805 which may be formed by aninternal wall of the routing chamber 713. When the extrusion nozzle 723is in the extrusion position, as illustrated in FIG. 8, constructionmaterial may flow from the main tube 711 through the valve door 803 intothe extrusion nozzle 723. On the other hand, when the extrusion nozzle723 is moved to the non-extrusion position, the valve door 803 may beclosed by virtue of it coming in contact with the valve closure surface805, thus preventing construction material from continuing to bedelivered to the extrusion nozzle 723. A similar valve may beincorporated into the routing chamber 713 to similarly regulate the flowof the construction material into the extrusion nozzle 719. Shut-offvalves of different types and/or in different locations may be used inaddition or instead.

A single extrusion nozzle may be used instead of the dual extrusionnozzle assembly illustrated in FIGS. 7( a)-(d) and in FIG. 8, such asthe single extrusion nozzle 601 illustrated in FIG. 6( a). In thisconfiguration, the interior and exterior surfacing layers may beextruded sequentially, rather than simultaneously. Alternately, asurfacing layer may only be applied to one side of an extruded surface.

The extruded layers which are surfaced and the extruded layers thatsurface them may be composed of different types of constructionmaterial. For example, the exterior of a building structure may besurfaced with extruded stucco, the internal extruded layer may beconcrete, and the internal surfacing layer may be plaster or some formof insulator material such as polyurethane. In another configuration,the external extruded surface may be concrete, the internal extrudedlayer may be foam (e.g., polystyrene), and the internal surfacing layermay be concrete.

In other configurations, only one of the vertical surfaces of anextruded layer may be surfaced. For example, a cementitious extrudedlayer may be surfaced with stucco or a foam extruded layer may besurfaced with concrete, or a concreted extruded layer may be surfacedwith foam.

In still other configurations, a wall have more than three layers may beextruded.

FIGS. 9( a) and (b) illustrate an extrusion nozzle configured to extrudean extruded surfaced layer that has a level top surface and a depth thatconforms to contours of an uneven ground surface below. Specifically, anextrusion nozzle 901 may include a tube 903 having a constructionmaterial inlet 905, a fixed outlet portion 907, a floating outletportion 913, fixed arms 915 and 917, floating arms 919 and 921, springs923 and 925, and a wheel 927. The configuration, operation, andalternate embodiments of the extrusion nozzle 901 illustrated in FIG. 9(a) and FIG. 9( b) may be essentially the same as those illustrated inFIGS. 5( a) and 5(b) and discussed above, except that the extrusionnozzle 901 may be of the type illustrated in FIG. 6( a), while theextrusion nozzle 501 may be of the type illustrated in FIG. 1( a).

FIG. 10 is a block diagram of an automated extrusion constructionsystem. This automated extrusion construction system may be used inconnection with any one or more of the extrusion nozzles and associatedslicing mechanisms discussed above. Conversely, the extrusion nozzlesand associated slicing mechanisms that have been discussed above may beused in connection with any other type of automated extrusionconstruction system, with any manual type of extrusion constructionsystem, and/or by a construction system that is partially automatic andpartially manual.

The automated extruded construction system may include one or moreextrusion nozzle assemblies, such as an extrusion nozzle assembly 1001.It may instead have no extrusion nozzle assembly. The automatedextrusion construction system may include one or more independentextrusion nozzles, such as an individual extrusion nozzle 1003. It mayinstead have no independent extrusion nozzles.

The extrusion nozzle assemblies, such as the extrusion nozzle assembly1001, may include a plurality of extrusion nozzles, such as the dualextrusion nozzle assembly 707 illustrated in FIG. 7( a). Each of thenozzles of the extrusion nozzle assembly 1001 may be configured to movefrom an extrusion position to a non-extrusion position using one or moreactuator mechanisms 1009. Again, reference may be made to FIGS. 7(a)-7(d) for examples.

The extrusion nozzle assembly 1001 may be moved to different positionsby a nozzle assembly positioning system 1005. The nozzle assemblypositioning system 1005 may be configured to controllably move theextrusion nozzle assembly 1001 to any position within three dimensionalspace. The nozzle assembly positioning system 1005 may be configured tocontrol the orientation of the outlet or outlets from the extrusionnozzle assembly 1001, as well as their position in space. To accomplishthis, the nozzle assembly positioning system 1005 may include one ormore robotic systems, such as one or more systems that have beendescribed in one or more of the patent and patent applicationsidentified above. The nozzle assembly positioning system 1005 mayutilize one or more sever motors, solenoids, nomadic actuators,hydraulic actuators, gantry positioning systems, and/or any combinationof these.

Construction material of any of the types described above may bedelivered to the extrusion nozzle assembly 1001 by a constructionmaterial delivery system 1007. The construction material delivery system1007 may include one or more construction material storage tanks, one ormore pumps, one or more pressure and/or flow regulators, one or moremixers, or any combination of these.

The extrusion nozzle 1003 may be any of the types of single extrusionnozzles that are illustrated in the drawings and discussed above. Theextrusion nozzle 1003 may include a slicing mechanism 1011, such as oneof the slicing mechanisms that are discussed above in connection withFIGS. 2( a) and 2(b) and 4(a) and 4(b).

The positioning of extrusion nozzle 1003 may be controlled by a nozzlepositioning system 1013. The nozzle positioning system 1013 may be anyof types of the positioning systems discussed above in connection withthe nozzle assembly positioning system 1005.

Construction material may be delivered to the extrusion nozzle 1003 by aconstruction material delivery system 1015. The construction materialdelivery system 1015 may be any of the types discussed above inconnection with the construction material delivery system 1007.

A controller 1017 may be configured to automate the control of thenozzle assembly positioning system 1005, the nozzle positioning system1013, the construction material delivery systems 1007 and 1015, and theactuator mechanisms 1009. For example, the controller 1017 may beconfigured to cause all of these components to function in anorchestrated manner so as to extrude a structure, such as a home oroffice building, layer by layer, in one or more of the various waysdescribed throughout this application. For example, the controller maybe configured to cause the nozzle positioning system 1013 to cause theextrusion nozzle 1003 to traverse a horizontal path, to simultaneouslycause the construction material delivery system 1015 to deliverconstruction material to the extrusion nozzle 1003, thereby causing afirst layer to be extruded. The controller 1017 may be configured tocause the nozzle assembly positioning system 1005 to cause the extrusionnozzle assembly 1001 to follow shortly behind the extrusion nozzle 1003and to extrude surface coatings on the first extruded layer that isextruded by the extrusion nozzle 1003, as illustrated in FIG. 7( a). Ifa corner is turned during this extrusion, the controller 1017 may beconfigured to cause one of the actuator mechanisms 1009 to move theinside nozzle in the extrusion nozzle assembly 1001 to a non-extrusionposition while the corner is being turned, as illustrated in FIGS. 7(b)-7(d).

After the first layer is extruded, the controller 1017 may be configuredto cause a material deposition system (not shown) to deposit ananti-inhesion layer on the surface of the first deposited layer, asillustrated in FIG. 3( b). Thereafter, the controller 1017 may beconfigured to cause the various components which have been described toagain extrude a second layer on top of the first layer as illustrated inFIG. 3( c) and, optionally, to again surface the vertical sides of theextruded layer, as illustrated in FIGS. 6( b) and 6(c).

After the second layer is extruded, the controller 1017 may beconfigured to cause the slicing mechanism 1011 under the control of thenozzle positioning system 1013 to slice through the second extrudedlayer, as illustrated in FIG. 3( c). The controller 1017 may beconfigured to cause the other components to continue extruding stackedlayers, to continue surfacing the inside and/or outside of each of thestacked layers, and to continue making slices for a rectangular opening,as discussed above and illustrated in FIGS. 3( c)-(f) and FIGS. 6( b),6(c), and FIGS. 7( a)-7(d). The controller 1017 may continue to causethese and similar actions to occur until the entire structure isextruded.

The controller 1017 may be of any type. The controller 1017 may includeone or more computer systems, including one or more processing system,movement sensing systems, memories, hard disk, use of interfaces,network systems, and computer programs. The controller 1017 may beprogrammed to construct an entire building or a substantial portions ofit in a completely automated fashion, with minimal or no userintervention.

The components, steps, features, objects, benefits and advantages thathave been discussed are merely illustrative. None of them, nor thediscussions relating to them, are intended to limit the scope ofprotection in any way. Numerous other embodiments are also contemplated,including embodiments that have fewer, additional, and/or differentcomponents, steps, features, objects, benefits and advantages. Thecomponents and steps may also be arranged and ordered differently.

For example, the nozzles that build external and internal extrudedsurfaces may deposit succeeding surface layers, one surface on the faceof the other, in multiple passes. These could be of the same ordifferent material. For example, an insulation material may be extrudedonto the internal surface during a first pass and plaster may beextruded over the insulation material during a second pass.

The phrase “means for” when used in a claim embraces the correspondingstructures and materials that have been described and their equivalents.Similarly, the phrase “step for” when used in a claim embraces thecorresponding acts that have been described and their equivalents. Theabsence of these phrases means that the claim is not limited to any ofthe corresponding structures, materials, or acts or to theirequivalents.

Nothing that has been stated or illustrated is intended to cause adedication of any component, step, feature, object, benefit, advantage,or equivalent to the public, regardless of whether it is recited in theclaims.

In short, the scope of protection is limited solely by the claims thatnow follow. That scope is intended to be as broad as is reasonablyconsistent with the language that is used in the claims and to encompassall structural and functional equivalents.

I claim:
 1. An automated extrusion construction system comprising: anextrusion nozzle configured to extrude construction material from anoutlet in the extrusion nozzle in a substantially horizontal directionagainst an elongated and substantially vertical surface that waspreviously extruded by means other than the outlet, and in a directionthat is substantially perpendicular to the surface; a nozzle positioningsystem configured to controllably move the extrusion nozzle to differentpositions; and a controller configured to direct the nozzle positioningsystem to move the extrusion nozzle across the substantially verticalsurface in a substantially horizontal direction while the extrusionnozzle is extruding the construction material so as cause asubstantially horizontal strip of the construction material to beextruded from the extrusion nozzle onto the substantially verticalsurface.
 2. The automated extrusion construction system of claim 1wherein the controller is configured to direct the nozzle positioningsystem to repeatedly move the extrusion nozzle across the substantiallyvertical surface in the substantially horizontal direction while theextrusion nozzle is extruding the construction material so as cause aplurality of substantially stacked and substantially horizontal stripsof the construction material to be extruded from the extrusion nozzleonto the substantially vertical surface.
 3. The automated extrusionconstruction system of claim 1 wherein the outlet is substantiallyrectangular in shape.
 4. The automated extrusion construction system ofclaim 1 wherein the outlet has a leading perimeter edge which is in thefront of and a trailing perimeter edge which is at the rear of theextrusion nozzle during its horizontal movement, and wherein the outletis configured such that the leading perimeter edge extends laterallyfurther than the trailing perimeter edge.
 5. The automated extrusionconstruction system of claim 4 wherein the outlet has a top perimeteredge which is at the top of the extrusion nozzle during its horizontalmovement, and wherein the outlet is configured such that the topperimeter edge extends laterally further than both the leading andtrailing perimeter edges.
 6. The automated extrusion construction systemof claim 2 wherein the substantially vertical surface is part of astructure that has a substantially horizontal upper surface and whereinthe controller is configured to cause an upper portion of the outlet toextend above the horizontal surface while the extrusion nozzle movesacross the substantially vertical surface in the substantiallyhorizontal direction.
 7. The extrusion nozzle of claim 1 furthercomprising a controllable pivot configured to allow the nozzle tocontrollably pivot with respect to the nozzle positioning system.
 8. Theautomated extrusion construction system of claim 1, wherein theextrusion nozzle includes an outlet from which the construction materialis extruded, the outlet having: a leading perimeter edge which is in thefront of and a trailing perimeter edge which is at the rear of theextrusion nozzle during movement in the horizontal direction; and atrowel that extends downwardly below a bottom portion of the outlet, thetrowel having a flat vertical surface that is sized and oriented tosmoothen a discontinuity between a lower edge of construction materialthat is extruded by the extrusion nozzle when moving horizontally and atop edge of construction material that was previously extruded that isbelow the lower edge.
 9. An extrusion nozzle configured to extrudeconstruction material in a substantially horizontal direction against anelongated and substantially vertical surface, the extrusion nozzleincluding an outlet from which the construction material is extruded theoutlet having a leading perimeter edge which is in the front of and atrailing perimeter edge which is at the rear of the extrusion nozzleduring movement in the horizontal direction, wherein the leadingperimeter edge extends laterally further than the trailing perimeteredge, wherein the outlet has a top perimeter edge which is at the top ofthe extrusion nozzle during the horizontal movement, and wherein theoutlet is configured such that the top perimeter edge extends laterallyfurther than both the leading and the trailing perimeter edges.
 10. Theextrusion nozzle of claim 9 further comprising a trowel that extendsdownwardly below a bottom portion of the outlet, the trowel having aflat vertical surface that is sized and oriented to smoothen adiscontinuity between a lower edge of construction material that isextruded by the extrusion nozzle when moving horizontally and a top edgeof construction material that was previously extruded that is below thelower edge.